Wire connector

ABSTRACT

A wire connector or terminal block including an arch-shaped pressure lever having two opposite leg portions resiliently deformable and expandable under pressure and a conductor plate mounted opposite the pressure lever, adapted to receive a wire end portion and resiliently hold it between the pressure lever and the conductor plate so that the wire end portion can securely be retained by the pressure lever which becomes resiliently deformable under any vibration or other external forces thereby ensuring better electrical properties of the connected portion.

UnIted States Patent [11] 3,

Saito Oct. 28, 1975 WIRE CONNECTOR 389.055 6/1965 Switzerland 339/272 R [791 w Yugo 9999 N9 8, Yayoni-cho, "213353? 511325 553222;; 339/272 R S-chome, Kakano, Tokyo, Japan [22] Filed: Dec. 27, 1973 I Primary Examiner-Joseph H. McGlynn Assistant ExaminerMark S. Bicks [21] Appl. No.: 428,736 Attorney, Agent, or FirmWenderoth, Lind & Ponack [52] US. Cl. 339/272 UC [57] ABSTRACT [5 l] Int. Cl. HOIR 7/14 A wire connector or terminal block including an h [58] new of Search 269/160; 339/93 263, 266, shaped pressure lever having two opposite leg portions 339/272 resiliently deformable and expandable under pressure and a conductor plate mounted opposite the pressure [56] References C'ted lever, adapted to receive a wire end portion and resil- UNITED STATES PATENTS iently hold it between the pressure lever and the con- 2,213,2s4 9/1940 Millermaster 339/266 F ductor Plate that the Wire end Portion can Sewrely 2,780,793 2/1957 Gambale I 339/272 UC be retained by the pressure lever which becomes resil- 2,997,688 8/1961 Nielsen 339/272 R iently deformable under any vibration or other exter- 3,727,171 4/1973 Coles 339/272 R- 131 forces thereby ensuring better electrical properties FOREIGN PATENTS OR APPLICATIONS of the connectedporfion- I 905,493 4/1945 France 339/272 UC 5 Claims, 5 Drawing Figures 2a 3a 1 A/ 5a k J 2/ 2i U.S. Patent Oct. 28,1975 Sheet1of3 3,915,545

U.S. Patent Oct. 28, 1975 Sheet 2 of3 FIG.2

FIG.3

US. Patent Oct. 28, 1975 Sheet 3 of3 3,915,545

contact resistance (mm befo e. vibration iest after vibrd iion test clamp [argue (kg'cm) There are knowna numberof wire connectors or terminal blocks. According to one prior art, a wire is fastened to a connector by winding the end portion of the wire around a screw and tightening the screw. In another prior art, a wire is retained on a conductor plate by tightening a screw. However, these present disadvantages since the wire connection easily becomes loose when the connector receives vibrations or other external forces. To avoid this, a spring washer is used, but does not meet the need as envisaged by the present invention.

In view of these, the present invention provides improvements over all the prior arts, in which an archshaped pressure lever and a conductor plate are provided to hold the end portion of a wire therebetween. The pressure lever is spring-loaded, and is resiliently deformable under vibrations or shocks, so that when the wire connector receives such vibrations or shocks, it prevents the connected portion of the wire from becoming loose and thus worsening the electrical properties thereof. Rather, it improves such electrical proper ties under this condition.

BRIEF SUMMARY OF THE INVENTION According to the invention, a wire connector is provided with an arch-shaped pressure lever opposite a conductor plate, both of which are in a variably spaced relation. The pressure lever is built of resilient metal material. The end portion of a wire is inserted between the two elements of the arch-shaped pressure lever, and is retained there by bringing the pressure lever nearer to the conductor plate by tightening a screw. With further screw tightening, the end portions of the pressure lever are expanded outwardly. This screw tightening is continued until the desired amount of pressure is attained. The amount of the tightening pressure depends on the shape, amount of elastic deformation or stability of the pressure lever, or the thickness of a wire used, and should preferably be over 8 kg/cm when using an arch-shaped pressure lever of 7cm high and cm wide built a hardened steel plate 1.2mm thick and 6.2mm wide. A pressure lever constructed according to the invention has two opposite leg portions; the end portions of these leg portions are bent outwardly and are expandable under the screw tightening pressure. The conductor plate is constructed of electrically conductive materials such as copper or copper alloy. The pressure lever and the conductor plate are mounted opposite each other in a variably spaced relationship, so that the distance between the two elements is adjustable by tightening or loosening the screw. This distance can be adjusted by moving either the pressure lever or the conductor plate, or both.

One object of the invention is to provide a wire connector or terminal block incorporating a pressure lever and a conductor plate for holding the end portion of a wire therebetween and maintaining the electrically connected portion in a good condition.

Another object of the invention is to provide improved electrical properties of the connected portion without adversely affecting or lowering the fastening pressure of the pressure lever when the connector or terminal block is wholly subjected to vibrations or shocks.

Still another object of the invention is to provide a connector or terminal block having a pressure lever the lowest end portions of which are outwardly expandable within the range of stability as the end portions are brought in contact with the surface of the a conductor plate, so that the end portion of a wire is resiliently held between the pressure lever and the conductor plate while a tightened screw is maintained at a constant pressure.

BRIEF DESCRIPTION OF THE DRAWING DETAILED DESCRIPTION OF THE INVENTION Now, the invention will be further described by way of examples only by reference to the accompanying drawing.

A pressure lever 3 is formed by an arch having two opposite leg portions, the lowest end portions of which are bent outwardly, and a top ceiling portion 3a having a hole for receiving a screw 1. A base 2 is provided for accornodating a conductor plate 6. The base member 2 has a hole 2b at the top 2a for engaging with the screw 1. The screw 1 passes through the hole at the ceiling 3a to reach the hole 2b for engagement therewith. In this manner, the pressure lever 3 is movably connected by the screw 1 to the base member 2. Two or more sets of the pressure lever 3 and the base member 2 thus combined are arranged in parallel with each other in an electrically isolated housing 8. The base members 2, 2 are arranged in parallel and are connected by a plate 2c on which a conductor plate 6 is mounted in such a manner that its surface is contacted by the two lowest end portions of the pressure levers 3., The screw 1 is loaded with a spring 4 between the top 3a and the top 2a to bias the pressure lever 3 to a normal state or upwardly. The lowest end portions of the lever 3 are then located away from kept clear of the surface of the conductor plate 6 to allow a wire 5 to pass therebetween.

The naked end portion 5a of the wire 5 is passed between the pressure levers 3 and the conductor plate 6 which are normally in a spaced relation to each other as explained above. Turning the screw 1 clockwise advances it toward the top 2a of the base 2 to engage with the internally threaded hole 2b With such tightening of the screw 1, the pressure lever 3 is forced against the spring 4 bringing the lowest end portions thereof into contact with the wire end portion 5a. Further screw tightening causes the lowest end portions of the lever 3 to press against the portion 5a, and to expand outwardly with the increasing pressure of the lever 3. Such expansion is represented by the change from the dotdash-lines to the solid lines in FIG. 4. Given vibrations or shocks in this state, the pressure lever 3 tries to stabilize, moving from a position indicated by solid lines to a position indicated by dot-dash-lines in FIG. 4, and naturally the pressure increases so that a better connection can be obtained. This also assures improved electrical properties of the connected portion.

Such improved electrical properties are supported by the following experiments which have been carried out and the results obtained therefrom as indicated in FIG.

Type of Wire Connector PRE- (20 Amp.) Test Conditions Room Temperature 23.0C

Humidity 72 7c Amplitude 4mm Number of Vibrations 2000 CPM Test Hour Consecutive 48 hours Directions of Vibrations Back and forth, horizontally and vertically Pressure Lever Hardened Carbonate Steel Plate l.2mm thick and 6.2mm wide 7.0cm high and 5.0cm open between the two opposite leg portions.

Under the above test conditions and with different tightening torques of 4, 6, 9 and 12 kg/cm, the test has been effected to obtain values of corresponding electrical contact resistance at the connected portion. The results show that the values are 0.4, 0.3, 0.25 and 0.25 mOhms respectively before giving vibrations while the values are 0.3, 0.2, 0.15 and 0.15 mOhms after giving vibrations. This supports the fact that the electrical properties of the connected portion have remarkably been improved.

Referring now to FIG. 4, the base members 2, 2 are arranged in parallel but are not connected by a plate 2c. This nevertheless serves the purpose of the invention.

In all the embodiments described above, the pressure lever 3 is adapted to move down the screw 1 tightening, but it is possible to move the base member 2 or both the lever 3 and the base member 2. There will be no need of the conductor plate 6 if the plate connecting the base members 2 is made of electrically conductive material.

I claim:

1. A wire connector for conductively connecting wires comprising:

a plurality of arch-shaped base member means comprised of electrically conductive material and arranged in parallel with each other with the open sides opposite each other for allowing said wires to pass therethrough;

first connecting means comprised of conducting material attached to the bases of said plurality of archshaped base member means for connecting said base member means to each other and for conductively supporting wires running through said base member means;

arch-shaped pressure lever means above each base member means having two resilient and opposite leg portions at the lowest ends thereof bent outwardly away from each other for fitting over the open sides of said base member means and contacting said wires; and

a second adjustable connecting means for connecting the top of each of said pressure lever means to the top of each of said base member means, whereby adjusting said second connecting means downward 5 y will cause said pressure lever means to move toward said base member means and will force said outwardly bent legs of said pressure lever means against said wire and said first connecting means.

2. A wire connector for conductively connecting l0 wires comprising:

a plurality of arch-shaped base member means arranged in parallel with each other with the open sides opposite each other for allowing said wires to pass therethrough;

first connecting means comprised of a joining plate attached to the bases of said plurality of archshaped base member means for joining said base member means to each other and a conductor plate of electrically conductive material located on said joining plate and running through said open sides of the plurality of base member means for conductively supporting wires running through said open sides;

arch-shaped pressure lever means above each base member means having two resilient and opposite leg portions at the lowest ends thereof bent outwardly away from each other for fitting over the open sides of said base member means and contacting said wires; and

a second adjustable connecting means for connecting the top of each of said pressure lever means to the top of each of said base member means, whereby adjusting said second connecting means downward will cause said pressure lever means to move toward said base member means and will force said outwardly bent legs of said pressure lever means against said wire and said first connecting means.

3. A wire connector as claimed in claim 2 wherein each of said pressure lever means has a hole in the top thereof for receiving said adjustable connecting means;

each of said base member means has an internally threaded hole in the top thereof for engaging said adjustable connecting means;

and said adjustable connecting means is comprised of a screw running through said hole in said pressure lever means and is engageably threaded into said internally threaded hole in said base member means.

4. A wire connector as claimed in claim 3 wherein said adjustable connecting means is further comprised of a spring surrounding said screw between said pressure lever means and said base member means for biasing the pressure lever means away from the base member means.

5. A wire connector as claimed in claim 2, further comprising electrically isolated framing means for housing said base member means, said first and second connecting means and said pressure lever means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. 3,915,545 Dated October 28, 1975 Inventor YUGO SAITO It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On page 1 of the patent, amend as follows:

-[76] Inventor: Yugo Saito, No. 8, 32. Yayoi-cho 3- chome, Nakano, Tokyo, Japan Signed and Sealed this seventeenth D ay Of February I 976 [SEAL] Attest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner of Parents and Trademarks 

1. A wire connector for conductively connecting wires comprising: a plurality of arch-shaped base member means comprised of electrically conductive material and arranged in parallel with each other with the open sides opposite each other for allowing said wires to pass therethrough; first connecting means comprised of conducting material attached to the bases of said plurality of arch-shaped base member means for connecting said base member means to each other and for conductively supporting wires running through said base member means; arch-shaped pressure lever means above each base member means having two resilient and opposite leg portions at the lowest ends thereof bent outwardly away from each other for fitting over the open sides of said base member means and contacting said wires; and a second adjustable connecting means for connecting the top of each of said pressure lever means to the top of each of said base member means, whereby adjusting said second connecting means downward will cause said pressure lever means to move toward said base member means and will force said outwardly bent legs of said pressure lever means against said wire and said first connecting means.
 2. A wire connector for conductively connecting wires comprising: a plurality of arch-shaped base member means arranged in parallel with each other with the open sides opposite each other for allowing said wires to pass therethrough; first connecting means comprised of a joining plate attached to the bases of said plurality of arch-shaped base member means for joining said base member means to each other and a conductor plate of electrically conductive material located on said joining plate and running through said open sides of the plurality of base member means for conductively supporting wires running through said open sides; arch-shaped pressure lever means above each base member means having two resilient and opposite leg portions at the lowest ends thereof bent outwardly away from each other for fitting over the open sides of said base member means and contacting said wires; and a second adjustable connecting means for connecting the top of each of said pressure lever means to the top of each of said base member means, whereby adjusting said second connecting means downward will cause said presSure lever means to move toward said base member means and will force said outwardly bent legs of said pressure lever means against said wire and said first connecting means.
 3. A wire connector as claimed in claim 2 wherein each of said pressure lever means has a hole in the top thereof for receiving said adjustable connecting means; each of said base member means has an internally threaded hole in the top thereof for engaging said adjustable connecting means; and said adjustable connecting means is comprised of a screw running through said hole in said pressure lever means and is engageably threaded into said internally threaded hole in said base member means.
 4. A wire connector as claimed in claim 3 wherein said adjustable connecting means is further comprised of a spring surrounding said screw between said pressure lever means and said base member means for biasing the pressure lever means away from the base member means.
 5. A wire connector as claimed in claim 2, further comprising electrically isolated framing means for housing said base member means, said first and second connecting means and said pressure lever means. 